Hazardous Gas Evacuation System

Abstract

A system and method for evacuating a harmful gas from an enclosed structure. The operation of the system is triggered by the detection of the harmful gas. Once triggered, normal air circulation through the HVAC duct is stopped. One or more separate evacuation blowers are activated and these pull the air withing the structure out. Some version are housed in a pass-through evacuation module within an existing HVAC duct. Other versions are housed within a combined register/evacuation module.

Claims

1. An evacuation system for evacuating a dangerous gas from an enclosed structure, said structure having an HVAC system with a duct, and said structure having a dangerous gas detector, comprising: (a) an evacuation module connected to said duct and connected to said enclosed structure; (b) an evacuation blower having an exhaust duct, said evacuation blower being connected to an evacuation blower intake on said evacuation module; (c) an entrance valve in said evacuation module configured to switch from an open state wherein said valve permits flow from said duct into said evacuation module and a closed state wherein said valve prevents flow from said duct into said evacuation module; (d) a system controller connected to said dangerous gas detector and said evacuation module; (e) said system controller being configured, in response to a detection of said dangerous gas by said dangerous gas detector, to close said entrance valve in said evacuation module and activate said evacuation blower; and (f) said evacuation blower being configured to pull air from said enclosed structure into said exhaust module and exhaust said air out through said exhaust duct.

2. The evacuation system as recited in claim 1, wherein said evacuation module comprises an air register.

3. The evacuation system as recited in claim 1, wherein said evacuation module is in-line in said duct.

4. The evacuation system as recited in claim 1, wherein said exhaust duct terminates outside of said enclosed structure.

5. The evacuation system as recited in claim 1, wherein: (a) said structure includes an attic; (b) said exhaust duct terminates in said attic: (c) said structure includes an attic fan configured to draw air from said attic and exhaust said air outside said structure; and (d) said system controller controls said attic fan.

6. The evacuation system as recited in claim 1 wherein said connection between said system controller and said dangerous gas detector comprises a tone detector connected to said system controller, wherein said tone detector is configured to detect a tone emitted by said dangerous gas detector.

7. The evacuation system as recited in claim 1 comprising multiple evacuation modules connected to said system controller.

8. An evacuation system for evacuating a dangerous gas from a building having a living space, said building having an HVAC system with a duct delivering air to said living space, and said living space having a dangerous gas detector, comprising: (a) an evacuation module connected to said duct and connected to said living space; (b) an evacuation blower having an exhaust duct, said evacuation blower being connected to an evacuation blower intake on said evacuation module; (c) an entrance valve in said evacuation module configured to switch from an open state wherein said valve permits flow from said duct into said evacuation module and a closed state wherein said valve prevents flow from said duct into said evacuation module; (d) a system controller connected to said dangerous gas detector and said evacuation module; (e) said system controller being configured, in response to a detection of said dangerous gas by said dangerous gas detector, to close said entrance valve in said evacuation module and activate said evacuation blower; and (f) said evacuation blower being configured to pull air from said living space into said exhaust module and exhaust said air out through said exhaust duct.

9. The evacuation system as recited in claim 8, wherein said evacuation module comprises an air register.

10. The evacuation system as recited in claim 8, wherein said evacuation module is in-line in said duct.

11. The evacuation system as recited in claim 8, wherein said exhaust duct terminates outside of said building.

12. The evacuation system as recited in claim 8, wherein: (a) said building includes an attic; (b) said exhaust duct terminates in said attic: (c) said building includes an attic fan configured to draw air from said attic and exhaust said air outside said building; and (d) said system controller controls said attic fan.

13. The evacuation system as recited in claim 8 wherein said connection between said system controller and said dangerous gas detector comprises a tone detector connected to said system controller, wherein said tone detector is configured to detect a tone emitted by said dangerous gas detector.

14. The evacuation system as recited in claim 8 comprising multiple evacuation modules connected to said system controller.

15. An evacuation system for evacuating a dangerous gas from a building having a living space, said building having an HVAC system with a duct delivering air to said living space, and said living space having a dangerous gas detector, comprising: (a) an evacuation module connected to said duct and connected to said living space; (b) said evacuation module being configured to evacuate air from said living space and exhaust said air through an exhaust duct; (c) an entrance valve in said evacuation module configured to switch from an open state wherein said valve permits flow from said duct into said evacuation module and a closed state wherein said valve prevents flow from said duct into said evacuation module; (d) a system controller connected to said dangerous gas detector and said evacuation module; and (e) said system controller being configured, in response to a detection of said dangerous gas by said dangerous gas detector, to close said entrance valve in said evacuation module and activate said evacuation module to evacuate air from said living space and exhaust said air through said exhaust duct; and

16. The evacuation system as recited in claim 15, wherein said evacuation module comprises an air register.

17. The evacuation system as recited in claim 15, wherein said evacuation module is in-line in said duct.

18. The evacuation system as recited in claim 15, wherein said exhaust duct terminates outside of said enclosed structure.

19. The evacuation system as recited in claim 5, wherein: (a) said building includes an attic; (b) said exhaust duct terminates in said attic: (c) said building includes an attic fan configured to draw air from said attic and exhaust said air outside said building; and (d) said system controller controls said attic fan.

20. The evacuation system as recited in claim 15 wherein said connection between said system controller and said dangerous gas detector comprises a tone detector connected to said system controller, wherein said tone detector is configured to detect a tone emitted by said dangerous gas detector.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0016] FIG. 1 is a plan view, showing an exemplary residential structure.

[0017] FIG. 2 is a plan view, showing an HVAC system used in the structure of FIG. 1.

[0018] FIG. 3 is a perspective view, showing an evacuation module configured for placement in an existing duct.

[0019] FIG. 4 is an elevation view, showing the operation of the evacuation module of FIG. 3.

[0020] FIG. 5 is an elevation view, showing the operation of the evacuation module of FIG. 3.

[0021] FIG. 6 is an elevation view, showing an alternate evacuation module that is incorporated in an air register.

[0022] FIG. 7 is an elevation view, showing the operation of the evacuation module of FIG. 6.

[0023] FIG. 8 is an elevation view, showing the operation of the evacuation module of FIG. 6.

[0024] FIG. 9 is a block diagram showing an exemplary control system for use in the present invention.

[0025] FIG. 10 is a block diagram, showing an exemplary control system used for an individual evacuation module.

[0026] FIG. 11 is a plan view, showing an exemplary installation of the inventive system.

REFERENCE NUMERALS USED IN THE DRAWINGS

[0027] 10 structure

[0028] 12 living room

[0029] 14 bedroom

[0030] 16 bedroom

[0031] 18 bedroom

[0032] 20 bathroom

[0033] 22 bathroom

[0034] 24 bedroom

[0035] 26 bedroom

[0036] 28 hallway

[0037] 30 air register

[0038] 32 air register

[0039] 34 air register

[0040] 36 air register

[0041] 38 air register

[0042] 40 air register

[0043] 42 air register

[0044] 44 air register

[0045] 46 air register

[0046] 48 carbon monoxide detector

[0047] 50 carbon monoxide detector

[0048] 52 fireplace

[0049] 54 space heater

[0050] 56 air handler

[0051] 58 air intake

[0052] 60 fixed duct

[0053] 62 fixed duct

[0054] 64 flexible duct

[0055] 66 flexible duct

[0056] 68 evacuation module

[0057] 70 duct coupler

[0058] 72 intake

[0059] 74 evacuation blower

[0060] 76 motor

[0061] 78 exhaust duct

[0062] 80 evacuation valve

[0063] 82 exit

[0064] 84 exit valve

[0065] 86 exit valve actuator

[0066] 88 entrance

[0067] 90 entrance valve

[0068] 92 entrance valve actuator

[0069] 94 ceiling

[0070] 96 evacuation intake valve

[0071] 98 evacuation blower input

[0072] 100 register/evacuation module

[0073] 102 coupler housing

[0074] 104 blower valve

[0075] 106 entrance valve

[0076] 108 entrance

[0077] 110 system controller

[0078] 112 processor

[0079] 114 memory

[0080] 116 I/O port

[0081] 118 I/O port

[0082] 120 I/O port

[0083] 122 tone detector

[0084] 124 HVAC interface

[0085] 126 I/O port

[0086] 128 I/O port

[0087] 130 I/O port

[0088] 132 I/O port

[0089] 134 I/O port

[0090] 136 evacuation module

[0091] 138 evacuation module

[0092] 140 evacuation module

[0093] 142 attic fan

[0094] 144 transceiver

[0095] 146 evacuation module controller

[0096] 148 I/O port

[0097] 150 processor

[0098] 152 memory

[0099] 156 I/O port

[0100] 158 I/O port

[0101] 160 I/O port

[0102] 162 valve actuator

[0103] 164 valve actuator

[0104] 166 evacuation duct

[0105] 168 evacuation duct

[0106] 170 attic fan

DETAILED DESCRIPTION OF THE INVENTION

[0107] The present invention is suitable for removing virtually any type of dangerous gas, as well as suspended particulates—such as smoke produced by a fire. The following examples pertain to the removal of carbon monoxide. However, the invention is not limited to the removal of this particular type of dangerous gas.

[0108] The invention incorporates one or more evacuation modules in the HVAC ducting of a building. A central function of each evacuation module is to pull the contaminated air out of an enclosed structure and exhaust it outside the living space of the structure. There are two main types of evacuation module. The first type is an “in-line” module—meaning that it is placed in an HVAC duct so that air traveling in the duct ordinarily goes completely through the evacuation module and continues onward in another segment of the duct. The second type is an “air register module” where the evacuation module is located at the end of the duct (and forms part of an air register feeding normal HVAC flow into the living space of a building).

[0109] FIG. 3 show an in-line version. Evacuation module 68 is located in fixed duct 60. Duct coupler 70 is part of the evacuation module. It mates to the duct on each end. Air normally flowing through duct 60 flows into the far end of duct coupler 70 and out exit 82 in the near end of duct, coupler 70 (“near end” and “far end” referring to the orientation shown in the view).

[0110] Closure valves are placed on the entrance and the exit of duct coupler 70. In the example shown, each closure valve assumes the form of a movable set of louvers. Exit valve 84 is shown in the view. It is open—as is the entrance valve—so that air is allowed to pass normally through the duct.

[0111] Evacuation intake 72 also connects to duct coupler 70. The evacuation intake connects to the living space within the building. In the version shown, the evacuation intake assumes the form of an additional air register in the ceiling of the room serviced by this particular evacuation module 68. The evacuation intake is ordinarily closed. It is only opened when evacuation of the air within the living spaces becomes necessary. Evacuation valve actuator 80 is provided to selectively open the valve allowing air into evacuation intake 72.

[0112] Evacuation blower 74 is provided to positively extract air through evacuation intake 72 when evacuating the air within the living spaces. Electrical motor 76 powers evacuation blower 74. The evacuated air propelled out of blower 74 is carried out exhaust duct 78. In the example shown the exhaust duct is a flexible tube connected to a larger exhaust system. In other examples the exhaust duct may simply be a part of evacuation blower 74 itself.

[0113] In FIG. 3 orientation “callouts” are provided for the view of FIG. 4. FIG. 4 is a sectional elevation view through the evacuation module 68 of FIG. 3. In FIG. 4, the view is taken from the side opposite the evacuation blower. FIG. 4 shows the state of the evacuation module when the HVAC is operating normally (and the inventive evacuation system is not operating).

[0114] Duct air passes into duct coupler 70 through entrance 88 and passes out through exit 82. A valve selectively closes the entrance and the exit. Entrance valve 90 selectively closes the entrance. It is actuated by entrance valve actuator 92. Exit valve 84 selectively closes the exit. It is actuated by exit valve actuator 86. Both valves in this example comprise a set of louvers. Both entrance valve 90 and exit valve 84 are shown in the open state in FIG. 4. HVAC air flows freely through duct coupler 70 as indicated by the arrows.

[0115] Evacuation intake 72 is closed off by evacuation intake valve 96—which in this example is another louver-type valve. The reader will note that the evacuation inlet 72 in this example assumes the form of an air register. It is mounted in an opening in ceiling 94. Evacuation blower inlet 98 feeds into the evacuation blower. It may optionally be closed by a valve as well. However, when the blower is off, an additional valve is not generally needed to stop unwanted flow through the blower.

[0116] The intent of the inventive system is to provide positive evacuation of the air within the living space of the building or enclosed structure when a dangerous gas is detected. FIG. 4 shows the operation when no such gas is detected. FIG. 5 shows the shift to the evacuation mode once a dangerous gas is detected. Entrance valve 90 and exit valve 84 are closed—stopping all air flow through the HVAC duct (even if the HVAC blower remains active). This stops any further distribution of dangerous gases by the HVAC system. Evacuation intake valve 96 is opened. Evacuation blower 74 (shown in FIG. 3) is energized. Air within the living space is drawn in through evacuation intake 72, in through evacuation blower inlet 98, and propelled by the evacuation blower out through exhaust duct 78. Thus, the evacuation module operates to remove the contaminated air form the living space within the building.

[0117] FIGS. 6-8 illustrate the second type of evacuation module—the “air register” type. In this embodiment the evacuation module is located on the end of a duct, rather than in-line. It is advantageous to combine the evacuation module with a conventional air register (though one could provide a separate module attached to an existing air register). FIG. 6 shows an exemplary register/evacuation module 100. Coupler housing 102 has an entrance configured to attach to a duct—in this case a flexible duct 64. Entrance valve 106 regulates flow into coupler housing 102 from the duct. The outlet of the coupler housing assumes the form of an air register 30 attached to an opening in ceiling 94. Exhaust louvers and other conventional air register features may be provided as well. These have not been shown for purposes of visual clarity.

[0118] Those skilled in the art will know that an air register is typically attached to more than just the drywall of a ceiling. It is typically attached to surrounding wood or metal structures to provide sufficient strength. This is true of the in-line evacuation modules as well. As these types of connections are well known, they have not been illustrated.

[0119] In the embodiment of FIG. 6, evacuation blower 74 is attached to the side of register/evacuation module 100. Motor 76 drives this blower in order to pull air in through evacuation blower inlet 98 and exhaust the air through exhaust duct 78. In the example shown, blower entrance valve 104 selectively closes the inlet 98. As mentioned previously, the blower entrance valve is optional, as the blower itself effectively blocks flow when it is not operating. A valve will block the air slightly more effectively, however.

[0120] FIG. 7 shows the exhaust module 100 operating in a normal state. HVAC air flows in through duct 64. Entrance valve 106 is open and the duct air therefore flows freely through entrance 108, through coupler housing 102, and out through air register 30. Blower entrance valve 104 is closed, preventing any flow into the blower.

[0121] FIG. 8 shows the same module when it is switched into the evacuation mode. Entrance valve 106 is closed, stopping all flow from the HVAC duct. Blower entrance valve 104 is open. Motor 76 is activated to power evacuation blower 74. The evacuation blower then draws the contaminated air out of the living space through register 30 and into the blower through evacuation blower inlet 98. The evacuation blower then propels the contaminated air out through exhaust duct 78.

[0122] The invention may be installed in an endless variety of structures. In some instances a single evacuation module will suffice. In other instances a dozen or more evacuation modules will be required. FIG. 11 shows an installation of in-line evacuation modules for the exemplary structure of FIGS. 1 and 2. An individual evacuation module 68 is provided for living room 12 and each of the bedrooms 14,16,18,24,26. In this application an evacuation module is added to only one of the two ducts in the living room 12. No evacuation modules are provided for the bathrooms. This selection concentrates on the sleeping areas—where the threat of insidious CO poisoning is greatest. In other applications more evacuation modules will be provided.

[0123] In the example of FIG. 11, the exhaust duct 78 from each blower is collected by an evacuation duct 166,168. Evacuation ducts 166,168 are run in the attic. These lead outside the building so that the contaminated air is carried well away.

[0124] Another approach is to propel the contaminated air out of the living space and into the attic—then propel it out of the attic. In this approach, the evacuation blower on each evacuation module simply exhausts the contaminated air into the attic. Attic fan 170 is activated to draw the attic air outside of the building.

[0125] It is possible to provide an independently acting control system for each evacuation module. As an example, a separate CO detector could be provided on each module and the actions of that module would then be determined by the readings of the single CO detector. It is preferable, however, to provide a centralized control system that is capable of directing the actions of multiple evacuation modules.

[0126] FIG. 9 provides a schematic view of an exemplary centralized control system. System controller 110 includes a processor 112 and an associated memory 114. The processor runs software configured to carry out the inventive process. Numerous input/output (“I/O”) ports are provided for the processor. In this example CO sensors 48, 50 are hardwired to I/O ports 118,120. The CO detectors provide an electrical trigger signal when CO gas is detected beyond a threshold amount. This information is sent to processor 112.

[0127] In some instances it is impractical to hardwire one or more CO detectors. In order to account for this possibility, system controller 110 is provided with tone detector 122. Tone detector 122 is set to detect the audible warning tone emitted by a CO detector. When tone detector 122 detects the warning tone, it creates a trigger signal that is sent via I/O port 116 to processor 112.

[0128] When processor 112 receives a warning signal from one of the CO sensors (or other dangerous gas detectors), it initiates the evacuation cycle. Each evacuation module 136,138,140 receives a trigger signal form the processor via respective I/O ports 126,128,130. If it is an installation containing an attic fan 142 configured to evacuate the attic, the attic fan is triggered via I/O port 132.

[0129] In this example system controller 110 is provided with a transceiver 144 that can provide two-way communications with processor 112 via I/O port 134. The transceiver can be used for many different purposes, such as updating the processor software. It can also be used to provide status messages to an external device such as a “smart home” system. HVAC interface 124 is provided so that the processor can communicate with the building HVAC system. In the event a dangerous gas level is detected it is preferable to switch the HVAC system off (in order to prevent further spreading of the dangerous gas). HVAC interface 124 can switch off the HVAC system. This function can also be carried out wirelessly using transceiver 144.

[0130] In the version shown in FIG. 9, each evacuation module has its own local controller. In such a system the system controller 110 only needs to send the trigger signal. The local controller on each evacuation module will then receive the trigger signal and perform a series of tasks. An embodiment of an evacuation module controller 146 is shown in FIG. 10. A trigger signal comes from the system controller and is received by I/O port 148. I/O port 148 delivers the trigger signal to processor 150. Processor 150 runs a program stored on its associated memory 152 to carry out the inventive process. I/O ports 158,160 provide actuation signals to valve actuators 162,164, which control the entrance and exit valves described previously (Some embodiments will have more than two valve actuators, so the example of FIG. 10 is only one example).

[0131] Blower motor 76 is a high-current device that is fed directly by AC line power in this example. Processor 150 provides a trigger signal through I/O port 156 to close the control coil on relay 162. Relay 162 connects the AC line power to motor 76—causing it to run.

[0132] Software running on processor 150 controls all the functions needed to transition the evacuation module from a normal state to an evacuation state. It will (1) Activate the suitable actuators to stop normal flow from the HVAC system, and (2) Activate the evacuation blower.

[0133] A back-up power source can be provided to the inventive system to guard against the possibility of power failure. A deep-cycle battery can provide DC power to the control circuit and—through the use of an inverter power supply—can provide AC power to the blower motors for a sufficient interval to evacuate the dangerous gas within a building (such as 30 minutes).

[0134] Although the preceding description contains significant detail, it should not be construed as limiting the scope of the invention but rather as providing illustrations of the preferred embodiments of the invention. Those skilled in the art will readily envision many other variations. As an example, an inventive system can be configured to evacuate a small, single room living space in a much larger structure. Alternatively, an inventive system can be configured to evacuate the entire structure. Thus, the language used in the claims shall define the invention rather than the specific embodiments described.